ORIGINAL: j.duncker

Get some 2 inch masking tape.
Lay up the sheets and push the edges together. \ 4 hands or lots of pins.
Apply tape over the join line.
Push sheet to edge of table so one piece of sheet is over the edge [ 90 degrees ] opening up the joint line.
Apply Testors aliphatic white glue TITEBOND?
Pull the sheeting back onto table.
Wipe off excess glue with a damp rag.
Hold down sheeting with weights or pins

If you need to do multiple sheets you can easily do this in one go. Just get everything taped up in advance.

Works for me!